Panarchy

Dr. Green

Complex Systems

• Change is episodic– Slow accumulation with sudden release– Cycles on different time scales

• Naturally lumpy world– Patchy and discontinuous world– Nonlinear processes are operative in scales

• Multiple states

• Systems are uncertain and unpredictable

Stability

• Engineering resilience– Efficiency– Control– Constancy– Predictability

• Mechanistic systems ontology

• Stability near equilibrium– Resistance to disturbance

Engineering Resilience

• Variability of natural systems can be controlled

• Consequences are predictable

• Sustained maximum production is the goal

• Single objective=only one equilibrium

• Other states can be avoided by proper controls

Stability

• Ecological resilience– Adaptiveness– Variability– Unpredictability

• Complex systems ontology• Far from equilibrium

– Instabilities can flip system into another stable configuration

• Multiple stable states

Nature as Flat

• A ball balanced at the top of a hill– No stability– Random processes– Destabilizing forces are primary

Nature as Balanced

• A ball at the bottom of a cup– Equilibrium– Negative feedback returns to equilibrium– Static world

Nature as Resilient

• A ball poised between multiple hills and valleys– Discontinuous events– Nonlinear processes

Nature as Evolving

• Nature is a raft– Add weight, it oscillates and returns to

another stable state– Too much weight under the raft, the raft sinks– Too much weight on top of raft, it will flip

• Loss of stability

Myths of Nature

• Nature is flat or anarchic– Strong stabilizing forces

• Nature is balanced– Strong destabilizing forces

• Nature as resilient– Can maintain a maladaptive state

• Nature as a complex adaptive system– Conserve the ability to adapt

Complex Systems

• Oscillation between accumulation and release of potential

• Oscillation between stability and instability

• Oscillation between vulnerability and persistencer

Complex Systems

• Potential available for change, gives range of options

• Degree of internal connectedness

• Resilience or vulnerability to unexpected shocks

Adaptive Cycle

• Exploitation Stage—rapid colonization or recently disturbed areas– Extensive dispersal abilities– Rapid growth– Scramble competition—the first to the prize

wins– Entrepreneurial stage

Adaptive Cycle

• Conservation—slow accumulation and storage of energy and material– Slower growth– Content competition—resources divided and

sequestered– bureaucracy

Adaptive Cycle

• Release– Overconnectedness leads to fragility– Fragility leads to rigidity and collapse

• Reorganization– Innovation and restructuring– Pioneer species

Adaptive Cycle

• Basic resources eliminated then system exists in a degraded state

• With sufficient carryover, the system goes through another cycle of development

Novelty

• Reorganization– Low connectedness and high resilience

• Novel combinations and low risk of systemic failure

– Leakiness– Greatest uncertainty

• Renewal• crises

r to K

• Exploiting opportunities in a variability environment

• Connectedness is low so external variability is important

• Winners expand and grow• Relationships develop that reinforce their own

expansion• Emphasis on control of variability• Long time period• Growth and stability phase

K to Omega

• Structural vulnerability

• Connections broken

• Regulatory controls weakened

• Strong destabilizing positive feedback

Omega to Alpha

• Sudden increase in uncertainty

• Unpredictable associations

• Maximizes invention and reassortment